Circuit-breaker.



A. M. TAYLOR.

CIRCUIT BREAKER.

APPLICATION r1150 MAR. 18, 1911.

Patented Dec. 14., 1915.

8 SHEETS-SHEET I.

A. M. TAYLOR.

CIRCUIT BREAKER.

AHPLICATION FILED MAR. 18, 1911.

V 1164,320. Patented 1190.1 915.

8 SHEETS-S 2.

MW? /y X 11170111151 8 SHEETS-SHEET 3.

Patented Dec. 14, 1915.

A. M. TAYLOR.

CIRCUIT BREAKER.

APPLICATION FILED MAR.1B. 19x1.

m I g A. M. TAYLOR.

CIRCUIT BREAKER.

APPLICAT'ON FILED MAR. 18. 1911.

1,164,320, Patented Dec. 14, 1915.

8 SHEETS-SHEET 4.

Anal

J V. r Fawn 51% w W 7 ,21 14/ A. M. TAYLOR.

CIRCUIT BREAKER.

APPLICATION FILED MAR. 18, 1911.

1,164,320, Patented Dec. 14, 1915.

8 SHEETS-SHEET 5.

Fla j;

Wadi.

A. M. TAYLOR.

CIRCUIT BREAKER.

APPLICATION FILED MAR.18.19H.

8 SHEETS-SHEET 6.

*VflmC.

Patented Dec. 14, 1915.

FIG. 9,

f .1 k V 3 .5 1 J A. M. TAYLOR.

CIRCUIT BREAKER.

APPLICATION r1120 MAR.18, 1911.

1,164,320. Patented D10. 14, 1915.

a SHEETS-SHEET 7,.

I ll/J A. M. TAYLOR.

cmcun BREAKER.

APPLICATION FILED MAR. 13' I9! I.

, 1,164,320, Patented Dec. 14, 1915.

a SHEETS-SHEET a.

In van/0 I wl'fhesses,

ALFRED MILLS TAYLOR, 0F BIRMINGHAM, ENGLAND.

CIRGUIT-BREE.KEE.

Specification of Letters Patent.

Patented Dec, 14, 1915,

Application filed March 18, 1911. Serial No. 615,308.

To all uiiom 2'23 may concern:

Be it known that I. rlnrnno M. TAYLOR, a subject of the King of GreatBritain, residing at Avondale, Ashficld Road, Kings Heath, Birmingham,England, have invented a nev and useful improvement in Circuit-Breakers,oi" Whichthe following is a specification. i

The primary obiject of this invention may be said to be the introductionin a circuit which is under the conditions of short circuit of aresistance or a reactance interjected by the motion of a switch which iscaused to operate in a period of time Which is only a 315 fraction ofthe time taken by the quickest known switches to operate.

A secondary object is the closing of a switch in a period of time muchquicker than present obtainable with known switches.

The invention is appl cable in most of its forms ther to direct currentcircuits or alternat g current circuits Wl h but small modiilcz on.

The principle upon which the switch opcrates is as follows: I is knownwhen a condu r carrying an electric current is 1 cnt b en; upon itsthere is mutual repulsio etween the two elements of the cur- W ou one ofthese elements he orin Oi a conductor rigidly A i s'ai "bl nsulators,and the other element to form of a hlads switch i e sac-called knifetype, the curca scd to travel dew i "opera 1 from the a the blade theabove mentioned is contact am. "1 1 e conouctoi A f .La 1 1 w is andattracted oy til current passing down the other side of each of thecoils in such a Way that it can move between the'two coils Withoutapproaching them, the force is then greatly increased, and by making theblade suiliciently light in its moving parts, a force producing anexceedingly rapid acceleration can be obtained. In certain cases whendealing with extra high tension currents it may be advisable in stead ofdirectly opening the high tension circuit, to throw into that circuit achoking coil, and in other cases it may be advis able instead ofswitching the choking coil into the circuit, to have the choking coilWound with a secondary coil which is normally closed'by an automaticswitch such as above described, and hein thus closed, the secondarycurrents by their deinagneti'zing action upon the choking coil, can bemade to cause the latter to act as a non-inductive conductor until theoperation of the said switch, when the reactance of the choking coil isimmediately thrown into the circuit.

The rapidity with which the electric current establishes itself on theoccasion of short circuit being" so very great, the time its opera; yminute, in fact, to this sort has to be which the switch has to performtion is correspond l c 'l a D successrui, a switch or capable ofcommencing; to break the circuit I n in an interval or J3 M l 01 ll $96110,.

reates; moms blade of the s possib e. s [111% reqi site Hy and c rcapacr Several l thods are Lication whereby tns blade c n he reducedbelow t of the of the cult, short circuit the c lreiit passin blade beintens'" he inve;

(Ft w v a series ct terms of the invention tor breaking the current inthe secondary circuit. Figs. 16 and 17 are diagrammatic views showingvariations of the forms oi'" the invention shown in Fig. 1. Fig. 18 is adetail view showing a term of the invention applicable to a directcurrent circuit; Fig. 19 is a detail view of a variation oi the circuitclosing mechanism. Fig, 20 is a similar view showing a variation of theinvention shown by Fig. 19. Figs. 21' and 22 are diagrammatic detailviews showing forms of the invention designed for increasing the numberot' contacts and resistances.

The switch may equally well be mounted in a horizontal position and tooperate in a horizontal plane, and for many purposes this is preferable.I

lteterring to Fig. 1, it will be noticed that the main current from thegenerator or other source to be protected, is led into the hinge of theswitch after passing through the lined coil a, after passing throughwhich is flows through the blade oi the switch Z) in an upward directionas indicated by the arrow 70 until it comes into connection with theprincipal contact jaw m from which it is led away by the conductor itback to the main circuit. it will be noticed that in addition to thecontact jaw we there are a number of smaller cont act jaws e e tc,arranged radially to clip on to the blade and between each of thesesmaller contact jaws there is a non-inductive resistance 7 7' 810.,which may consist of a thin strip suited for dissipating the heat veryrapidly. will further be. noticed that there are two or more principalcontact jaws n and 0 arranged circumferentially with reference to themotion of the switch, and that between these jaws there are other muchheavier non-inductive resist ances such as d d Neglecting for the momentthe other portions of the switch, and considering the action of thoseportions which have been up to the present mentioned, we will nowconsider the actions that obtain when the switch is blown out of itsposition by the intense magnetic field in which it is placed. Thismagneticlield, due to the coil a is at right angles to the paper, andpasses across the blade Z) of the switch. The field can be intensifiedvery greatly by the employment of suitable laminated iron stampingsarranged to complete the magnetic circuit around the back of the panelor framework which carries the switch. The etlect 'oit'tl is will be thwhen blade Z) the switch is blown outward as shown by the large arrow,due to the repulsive action, the arcs formed at small contacts 6 6 etc,are in the intense magnetic field in which the blade itseli moves, withthe result that there is what is known as a very tense m gnetic blow outaction l M th current passing across these arcs. llhese contactsmoreover, together with the whole switch, can be immersed in an oil bathwith the additional efiect of quenching the arcs at these contacts.Another important effect obtained Before the blade 0 has parted companywith the bottom contact oi the radial line of contacts, the top of thesaid blade has made contact with the second of the circumferentialcontacts a. lhere is therefore no total interruption of the current atany point from the time of the blade leaving the contact at until itreaches the contact n. The

lads in tact would be designed of a sufiicient width to come intocontactwith the contact jaws a before it left the contact jaws m. Thevalue of this combined arrangement of radial and circumferentialresistance is that the current is induced to flow through thenon-inductive resistance at, not

suddenly, but by a succession of steps each of which increases thedifference of potential applied to the non-inductive resistance d, by anequalamount. There therefore tends to be no sparking whatever when theblade leaves the contact jaw no, because the whole current is not forcedsuddenly into the resistance G3,. Should it be desired to add additionalradial contacts a second line of these can be added radially between theprincipal contact a and the hinge of the switch. 5

it will be noticed that the blade ot the switch is provided with acranked end 3 to which is attached a spring 70, the angle of the crankbeing so chosen that when the switch'is in the closed position thespring tends to hold it in thisposition against the magnetic repulsiveaction of the current ordinarily circulating in the switch. When,however, the blade of the switch opens be- Elli yond certain angle, thepoint or" the application ot the force ot the spring passes over thedead center and tends to keep the switch opened. lit, however, is notdesired that should happen, the spring can be arranged so that tends toclose the switch from all open positions.

j will be noticed thatthere are sundry insulating barriers c 0,, do,shown in Fig.

These made of a refractory and ina j J:

sach as mica, and are ior one i'roin travcling upward along the line ofcontacts 6, 22

etc, instead of the spark at each contact bethe blade 5 moves out fromthe switch, the

oil could not, by virtue of its inertia, occupy the space left by theblade sufficiently rapidly, and a partial vacuum would be formed behindthe blade, whichwould leaveopportunity for an arc to commence. By thearrangement indicated the arc is entirely crushed out, and is given noopportunity to get a start.

Coming now to the method by which the current through the blade when ashort circuit occurs is enormously increased above that even in theshort circuit, it will be noticed that the main line current is causedbefore entering the fixed coil (1 of the switch, to circulate around theprimary coil .9 of a transformer conventionally illustrated. (which mayor may not have iron. in its magnetic circuit), and the secondary r ofthis transformer is so wound that the current induced in it is thedesired multiple of the current passing through the primary coil 8. Thissecondary current is led into the bottom. and top of the switch blade bymeans of the hinge at the bottom and the contact jaw 17 at'the top, andthe connections are so led that the current is made to traverse theblade in the same direction as the main line current, and so to multiplythe effect on the blade in proportion to the combined current. Bydispensing entirely with iron in the small transformer r s, the currentfrom the secondary coil 1* may be made as nearly absolutely synchronouswith the main line current as we please. The transformer 1" s will notrequire to be at all large, since the only energy it has to generate isthat due to the energy being lost in the blade 7; of the switch, andsince the resistance of this is low and the reactance cannot be veryhigh, the cost of this small transformer will not be appreciable.

Vith a view to still further reducing the weight of the blade 6, owingto its having to carry the main line current continually, I may arrangea second primary coil t supplied from a source of E. M. F. through aresistance j, and arranged under normal. working to somewhatover-compensate for the ampere turns due to the primary coil 8 in such amanner as to produce a small flux through the core of the transformerwhich shall be in the opposite direction to the flux which is to beproduced by the main primary coil under conditions of short circuit.

The E. M. F. in the secondary coil r will therefore be in the reversedirection to that in which it is intended it shall operate underconditions of short circuit, and this E. M. F. will produce under normalconditions a current downward through the blade (see Fig. 1), opposingthe flow of the main line current, and incidentally assisting the fiowof the main line current through the second ary coil r instead ofthrough the blade, thus relieving the blade of the necessity of carryingany appreciable current under normal working conditions, and thuspermitting its mass to be reduced. In order to prevent the I auxiliaryprimary winding 2,, which is energized by the E. M. F. of the generator,from operating as a closed secondary coil (discharging into thegenerator) at the time of short circuit, the resistance or reactance jis arranged to abstract a considerable proportion of the E. M. F. of thegenerator, only a small proportion being thus left to be applied to the0011 t. When the short circuit occurs, and 2, becomes the generatingcoil it is unable to produce a large demagnetizing current on account ofthe large resistance or reactance j.

In Fig. 3 a detail perspective view of a simple form of the inventionhas been shown as an actual structural device to enable the constructionand operation to be readily determined by inspection. The principle ofoperation is the same as described above in connection with Figs. 1, 2,and 3. The current from the generator G after passing through the fixedcoil a, enters the switch blade I) at the hinge and passes through theblade Z), contact m and conductor 15 to the line. The return circuit isthrough the conductor 16 to the generator.

\Vhen the switch blade is thrown to open position by the magnetic fieldbetween the poles of the electro-magnet core a on which the coil or iswound, the blade first leaves the contact jaw m, and then the smallercontact jaws e 6 etc., in succession, so that the noninductiveresistances f f etc., connecting the contact jaws are successivelyintroduced into the circuit in series. For the sake of simplicity ofillustration only a single radial series of resistances is shown in thisview. Additional resistances and contacts may be used as disclosed inconnection with Figs. 1, 2 and 3. The operation of the transformer r s,the auxiliary coil t, and the reactance j, in reducing the normalcurrent through the switch blade and enormously increasing the currentthrough the switch blade under the conditions of a short circuit, havebeen fully set forth in connection with Figs. 1, 2 and 3.

Referring to Fig. 4i, an instantaneous switch of the type shown in Figs.1, 2, and 3, but'mounted in a horizontal position, is shown, andarrangements are shown wheretill by such a switch could be closed from aswitch board at a distance, and could be yet entirely free to openautomaticallywithout increasing to any appreciable degree the inertia ofthe parts which have to be moved rapidly. A similar arrangement could begot out in which the blade of the switch moves in a horizontal planeinstead of a vertical plane as in ig.

Referring now in detail to Fig. 4, it will be seen that the blade atcarries at its entremity a piece 6 hinged as shown, and con trolled by aspring in such a way as to make it take up a position in line with the"rest of the blade unless extreme forces are brought to bear upon it. A.link d engages as shown with the underside of the piece 6 of the bladeand this-link is carried by a rod passing through the roof of the boxwhich carries at its extremity a catch 6. Inside the bOX is a spring fwhich is compressed when the switch is being closed.

For the purpose of engaging with the catch 6 from the operating board, abell crank g pivoted at g is provided to the left hand end of which atrigger it provided with a spring j is pivotally attached. The trigger71, carries a tail piece is, and when the crank g is rotated in thedirection indicated, by the operating rods connecting with the mainswitch board, this tail piece It comes into contact with the fixed stop'Z which causes the trigger piece which had been previously engaged withthe catch 6 to lose contact with the catch e, and the link at (to whichthe catch is attached as already explained) immediately falls to itsbottom position under the action of the spring 7". The blade at,however, does not follow the link d, the slot in the link permitting thelink to move independently of the blade, and the blade remains in theclosed position, held there partly by the triotion of the contact jaws mand partly by the spring a. 'W hen, now, it is desired to again closethe switch from the switch board the crank g is rotated backward untilthe trigger piece 72, engages with the catch-e, and.

the switch is then ready for closing. lt will be understoodthat theswitch shown in Fig. is adapted to have combined therewith automaticmeans for opening switch as shown in l and other figures.

@ther methods of decreasing the weight of blade, alternative to themethod proposed in Fig. l are shown in l igsh, 6, 7, 8, 9.

lln Fig. is shown an arrangement in which the fixed coil a. whichdeflects the blade 5 is shown in a parallel circuitto the blade with aview to normally carrying the bulk of the current. In order to keep thecurrent out of the blade in normal working a stationary reactance coillit, which may be mounted on the same magnetic core as the it from theblade.

iaeasao main deflecting coil, is put in series with the which is,further, insutficiently laminated,

the'result being that with the ordinary rate of change of induction,this core answers sulliciently to keep the current out of the blade; butthat'with the extreme rate of change of induction obtaining on shortcircuit, the coilis unable to keep the rush of current from the blade.Both in this case and in Fig. 5 the blade of the switch can be utilizedto disconnect the main fixed coil or from the circuit before the switchblade interrupts the main circuit, and in order to reduce sparking fromthis cause, a non-inductive resistance may also be placed in parallelcircuit with the fixed coil.

, In Fig. 7 is shown another arrangement for reduping the currentnormallyv flowing through the blade of the switch. A reactive coil R isshown here as-in Fig; 6 in series with the blade, but instead ofdepending upon the current passing through the blade to give thereactive efiect, a second coil R connected with a source of E. M. E. iscaused to induce in the reactive coil aback E. M. E

through the fixed coil a, and thus to abstract TV hen a short circuitoccurs, there is no E. M. l between the mains, and the two E. M. E.coils behave as partly closed secondaries, facilitating the flow ofcurrent through both branches of the circuit. I

ln Fig. 8 is shown an arrangement for a similar purpose where no E. M.E. coil is available. Two reactive coils T and U in this case areinserted in series with the fixed coil a, as shown, and the main linecurrent is taken around a second winding U wound over one of these,inducing an E. M. E. in such direction as to force current through thefixed coil as. The other reactance coil T is wound on a core which isinsufiiciently tired coil itself is shunted, as. shown in Fig.

9, by a reactance coil V over which is wound a coil V supplied from asource of E. M. F. tending to induce in the reactive coil V an E. M. F.which sucks the current through this coil in preference to going aroundthe fixed coil In Figs. 10 to 15 is shown a series of arrangements forbreaking the current in the secondary circuit rather than in the primarycircuit. The simplest of these is shown in Fig. 10 and requires noexplanation. The switch of the type shown in Figs. 1, 2 and 3 is simplyconnected in the secondary circuit of a large transformer whose primarycircuit is in the main line high tension circuit.

In Fig. 11 is shown an arrangement whereby a single switch in the hightension circuit can introduce reactance into the three phases of thesaid circuit. Conductors 1, 2 and 3 from these three phases are ledaround the core 4 of a transformer in such adirection that when thecurrents in the three phases are equal, no magnetic flux is produced,but when an out-of-balance current flows, due to a fault on any onephase, a very heavy flux is immediately induced in the iron, and a largesecondary current is-thereby generated in the coil 5 which in turn actsto operate the instantaneous switch a, I).

In Fig. 12 another arrangement is shown more suitable for operating witha short circuit on all three phases than with an out-ofbalance current.One of the three primary windings 1, 2, 3, as for example the winding 2is arranged to have fewer ampere turns than the other two, but this iscompensated for by a coil 6 sup lied from a source of E. M. F. and normaly connected up to this source of E. M. F. by means of the instantaneousswitch a, b, which is itself supplied from a secondary coil 5 on thesaid transformer. When now a short circuit occurs, the pressure goesdown and the arrangements are thrown out of balance magnetically, withthe result that a large current is generated in the secondary coil 5,which operates the instantaneous switch in the predescribed manner.

In Fig. 18 is shown an arrangement for causing the current in thesecondary coil to run up at a greater rate than would be the case bydirect induction from the primary circuit. In this arrangement atransformer is shown, consisting of three limbs, the windings on the twoouter limbs of which are in the primary circuit, and are connected inparallel one with the other. On the central limb is wound a coil 0capable of abstracting flux from the one outer limb, and adding it tothe other outer limb.

- When the rush of current comes, the main line current which traversesthis central coil operates to greatly increase the flux on say the righthand limb of the transformer,

with the result that the current generated in the secondary coil shownon this right hand limb is greatly increased, and the switch opens themore rapidly. In order to prevent the central coil from producing thiseffect in the normal workin another coil cl supplied from a source of M.F. is also wound on the central core, and in such a di rection that whenthe E. M. F. is normal, the effect of the main line current on thecentral core is .practically eliminated. When the short circuit occurs,the efiect of the E. M. F. coil is relatively very small, and the actionabove alluded to can take place.

In Fig. 14 is shown an arrangement for increasing the force on the bladewhere it is desired to break the high tension circuit in the threephases of the supply to a consumer if an out of balance current occursin any one phase. The object of the arrangement shown here as againstthat shown in Fig. 11 is that whereas Fig. 11 requires a very largetransformer in order to insure the requisite choking efi'ect in order tokeep down the current in the main line, Fig. 14 can be operated with avery small transformer, since in this case, the current induced in thesecondary coil is caused to open the switch and break the primarycircuit, and thus no reactance is required to be introduced in thetransformer itself. In the arrangement shown, the secondary coil has, ofcourse, to be disconnected by means of the switch from the circuitbefore the primary circuit is opened by the switch. This is easilyarranged by means of the contact (0) as shown.

In Fig. 15 We have the same arrangement as Fig. 14 except that amagnetic circuit containing no iron, or containing a large air gap, issubstituted for that containing iron without an air gap.

In Figs. 16 and 17 are shown alternative arrangements to Fig. 1 to meetthercase where it is required to permanently insert a large choking coilin the circuit on the occasion of a short circuit, as for instance,where, in a'large generating station, it is desirable to break up thebus bars into two or more sections, and connect these by choking coils.By means of the present invention the choking coil can be normally cutout of the circuit and automatically thrown into circuit without unduerise of potential. When the choking coil is only to be used for thepurpose of restricting a short circuit current for a short period, theabove arrangement greatly reduces the cost of the copper in the saidchoking coil.

Referring to Fig. 16 it will be seen that a choking coil 8 having a verylarge num ber of tappings is connected in place of the non-inductiveresistances f f. etc., of Fig. 1, and these sections are thrown in rapidsuccession by the opening of the switch.

The switch itself is precisely similar in-its arrangement to that shownin l ig. 1.

Fig. 17 shows an alternative 'method which avoids the construction of achoking coil with a number of tappings, which might lead to breakdownsin the insulation, and retains the non-inductive resistances f f etc.,shown on Fig. l but substitutes the choking coil 9, which may be in twoor three sections in place ofthe circumferential resistances (Z, d, ofFig. 1. By this arrangement the choking coil has successive increme'ntsof E. M. applied to it, causing the current to rise in correspondingstages, instead of being called upon to instantly receive the whole ofthe line current. if found desi able, a second line of radial contactsas shown may be employed, or even a third line, the choking coil beingin this case divided up into two or three sections, each of which is putacross a pair of the circumferential contacts as shown for 2 sections.

lln Fig. 18 is shown an arrangement more particularly applicable to adirect current circuit enabling the mass of the blade to be reduced bythe device of splitting the main current (where large) among severalblades in parallel circuit, the cooling surface for a given amount ofrigidity in the blade being thus increased, and more current being thuspermissible to be passed through the blade. The blades move in veryintense fields which are really all one field, the air gaps betweenblade and blade being bridged magnetically by the blocks marked N. S. Asingle pair of exciting coils was shown, may thus be utilized to providethe held for a number, of blades magnetically inseries anda magneticblow out is also provided for the arc of ample strength. The magneticcircuit is of course, completed by a solid loop of iron around the backof the switchboard. ln certain cases it may be desirable to couple theblades in series with one another, but where they are coupled inparallel circuit, they may with advantage be carried on a single hollowshaft, to which they are keyed as indicated, so that they all operatewith the same velocity. Non-arcing barriers are interposed near thebreaking contacts between bladeand blade.

lln Fig. 19 is shown an arrangement for instantaneously closing acircuit by the action of current from a source of direct cur- K rentsupply energizing a coil so as to produce a very strong held, in whichthe blade is placed as indicated. 'lhis blade makes contact at itsmovable extremity with the contact jaws u and by means of thesecontactjaws or brush and the hinged contact at the other end of the blade acurrent of very large amount may be momentarily sent through the bladefrom a source of ens y such as say, two or three cells of a storagebattery v as shown, the circuit being closed by i ea-sac means of aswitch to. The interaction be- E. M. l provides a force of great amount(which can be increased by the use of iron in the circuit) propellingthe blade with great velocity toward the high tension circuit to beclosed. It can be arranged if de sired that the blade of the switch isprolonged at the hinged end, and that this prolongation only makescontact with the jaw during the first part of the motion of the blade,so that the low tension circuit is disconnected entirely from the hightension circuit before the latter is closed.

lln Fig. 20 a somewhat similar arrangement is shown, but in this casethe switch is closed by means of an alternating current. A smallalternating current transformer rs has its primary circuit energized byan alternating current which passes through the fixed coil a and isconnected direct on to the mains. lln the secondary coil r of the abovetransformer a very large current of very low voltage is generated whichis sent directly through the blade I) of the switch in the.

same way as was the battery current in Fig. 19. @n closing the switch 10the blade 6 of the automatic switch is propelled with great force towardthe main line contacts.

Referring generally to the whole of the arrangements shown throughoutthis specilt cation for the operation of the instantaneous switch, itmay be stated that though referring principally to the useof alternat'ing current, the arrangements will all hold with direct current providedthat'the flux due to the normal current traversing the coils of thetransforn'iers, etc., does not produce anything approaching saturationin the iron. 'lo efi'ect this result the iron circuit should beincomplete, and in some cases it will be desirable to avoid an ironcircuit altogether. Fig. 15 for instance, is an arrangement that wouldbe employed as well with direct as with alternating current.

It will be understood that, where the main line currents (moreespecially in the case of direct currents) are so large thatdiiiiculties would be encountered in making the switch blades andcontacts suthciently heavy to carry such currents, the method ofemploying a closed secondary coil shown in Figs. 10 to 15 can beemployed with the difference that the number of turns in the secondarycoil can be increased above that in the primary, and the operatingcurrents in the secondary consequently reduced. though the ll M. F. tobe broken will. of course, be correspondingly increased. Thearrangements of the automatic switch working in oil permit, however, ofthese higher voltages more readily dealt with than the higher currents,so far as the tarsal-ring the concerned.

its

ing split up equally among them.

menses As has already been noted, if an increased number of radialcontacts above that shown in Fig. 1 were required, they could beobtained by providing one or more radial lines of contacts, the switchblade as it moved outward coming successively into contact with theseradial lines of contacts and their resistances.

Figs. 21 and 22v illustrate a modified construction for effecting thesame result; that is, increasing the number of contacts and resistances.In this arrangement, I utilize two or three blades, which, with theirlines of radial contacts, are separated only by the space necessary toaccommodate the fixed coils which produce the. magnetic field, which isarranged to traverse the whole of the blades acriatz'm. in the moregeneral case, namely, that in which the main line current iscomparatively small and the voltage high, I connect the two, or three,blades electrically in series and I so arrange that the three, or two,blades shall be driven out of their seats all at precisely the samespeed, that is, that they shall maintain their relative angularpositions as they move outward. The way in which this is performed willbe best understood from the details of the arrangement given on thedrawing.

Fig. 2l-shows the three blades 5 b 6 mounted side by side which, withtheir lines of contacts, 6, e, e, are operated by the fixed coils a a (1three blades being assumed to be employed.

Contacts g 9 51 ,9, are arranged in connection with the secondary coilor coils r r 1, of the auxiliary transformer or transformers, 7' 8 7' 81' .3 (see Fig. 22), the blades 6 b 5 as they move outward, passingthrough these contacts.

Referring to Fig. 22 which is a diagram -matic view of the electricalconnections, it

will be seen that, between these contacts g g 9*, there are arrangedresistances, of very low value, and large currentcarrying capacity,suitable for receiving the heavy currents supplied by the secondary coilor coils r r 7- of the auxiliary transformers.

It will also be noticed that the primary coils s s a of the threeauxiliary transformers, are arranged in parallel circuit with oneanother, the main line current be- It will further be noticed that ineach branch there is a pair of haltcoils, (4 included in series with theprimary coil of the auxiliary transformer.

t should be mentioned that the contacts g g g are made very narrow in acircumferential direction, so that a very small movement of the bladesif, 6 5 can rapidly insert resistances in the secondary circuits of theauxiliary transformer.

The is as ache-ave:

'rush of current comes, it divides itself consequence driven out withgreat force. Should, however, one blade move more rapidly than theothers, owing to less friction in its contacts, or other cause, therewill be a greater resistance in the secondary circuit supplying thatblade, with a consequent diminution of force, thereby tending to slowdown the speed of the blade. Also, owing to the secondary current beingless, the primary current, and consequently the current in the fixedcoil, will also be less, the demagnetizing eflect of the secondary beingreduced. Consequently the speed of motion of the blade will be doublyretarded. By this means any blade tending to move unduly rapidly is keptback in such a manner that the other two blades can obtain the sameangular position.

, aving now particularly described and ascertained the nature of thesaid invention, and in what manner the same is to be performed, Ideclare that what I claim is:

1. In a switch adapted for instantaneous automatic operation underexcessive momentary currents, the combination of relatively movableelements of the circuit positioned to have a reacting force appliedthereto by the current therein, said elements movable relatively to eachother by'the reactive force of the current therein, and means operablewhen the current in the circuit is increased to cause the reactive forcebetween said elements to increase in a greater ratio than the product ofthe increased current in said elements.

2. In a switch adapted for instantaneous automatic operation underexcessive momentary currents, the combination of a portion of thecircuit arranged to produce a mag netic field when a current flows inthe circuit, a switch blade in said magnetic field and forming part ofthe circuit, and means brought into operation by an increase of currentin said circuit to cause the strength of the magnetic field to increasemuch more rapidly than the said current increase, and thereby produce anintensely powerful magnetic field when a heavy current flows in thecircuit.

3. in a switch intended for automatic operation under excessivemomentary currents, the con'ibination of a circuit comprising adeflecting coil, stationary contact, and a switch blade in engagementwith said contact and movable away from said co the rearive 1? rec ofelectrically connected without material resistance therebetween andthereby having substantially the same potential, the blade and coilbeing in close proximity without tendency to spark across from one tothe other, and means brought into operation by an increase of current inthe circuit to multiply the intensity of the increased current in thecoil and blade, and thereby multiply the reactive force between the coiland blade tending to move the blade away from its contact.

l. lln a switch intended for automatic instantaneous operation underexcessive momentary currents, the combination of a movable switch blade,a deflecting coil'in circuit with the switch blade, and atransformerhaving a primary winding in circuit with the switch blade, and asecondary winding arranged to discharge into the switch blade, thetransformer having also an auxiliary Winding, which auxiliary winding isarranged to reduce the reactive effect between the switch blade and thedeflecting coil during the normal flow of current.

5. In a switch adapted for instantaneous automatic operation underexcessive momentary currents, the combination of a switch blade, areactive coil arranged to react on the blade and move it to openposition when subjected to an excessive current, inductive meansenergized by the said current in part of the circuit separate from saidcoil to multiply the current in the switch blade, and a till springarranged to hold the switch in both open and closed position;

6. ln a switch adapted for instantaneous automatic operation underexcessive momentary currents, a switch blade, means to cause anexcessive current in the circuit toreact on the blade and open thelatter, inductive means energized by the said momentary currents tomultiply the current in the switchblade and thereby multiply thereactive power tending to open the blade and means to automaticallyreturn the blade to closed position if the short-circuit clears itselfbe fore the blade reaches a predetermined point in the openingmovement.

7. lln a switch adapted eration under excessive momentary currents, thecombination of a switch blade and a stationary switch contact tocooperate with the rapidly than in the remainder of the circuit.

8. ln a switch adapted for automatic operation under excessive momentarycurrents, the combination of a switch blade and a stationary switchcontact to ooperate with the blade, means in circuit with said blade tore act on the said blade, and an intensifier associated with said bladeand causing the curfor automatic oprent in the blade to increase morerapidly than the main current in the circuit.

9. The combination of a switch blade, a coil in circuit therewith andpositioned to react thereon when a current flows, a shunt circuit acrosssaid switch blade, and a transformer comprising a primary coil in themain circuit and a secondary coil in said shunt circuit, the shortcircuit being so connected across the switch blade that upon an overloadthe current through said shunt circuitwill react on the current, in theblade so as to tend to move the blade to open position.

10. In circuit breaking apparatus, the combination of a movable switchmember, a

coil in circuit therewith and positioned to V react thereon when acurrent flows, a transformer comprising a primary coil in the maincircuit and a secondary coil connected ina shunt circuit across saidswitch member, and a second primary coilreceiving current from aseparate source and reacting on said secondary coil, said secondary coilbeing so connected thatupon an overload, the current therein will be ina direction such that the reaction between said secondary coil andswitch member will tend to move the latter to open position.

11. ln a switch intended for instantaneous automatic operation underexcessive momentary currents, the combination of a movable switch blade,a deflecting coil, and a transformer having a primary-winding connectedin circuit with the switch blade, and a secondary winding connected todis charge into the said switch blade, said secondary winding arrangedto magnify the reactive effect between the said switch blade and thedeflecting coil, and thus, for a given short circuit current, todiminish the time taken to open the switch; also the combinationtherewith of an auxiliary primary winding of the transformer arranged tocause theesecondary winding of the said nected in clrcuit with theswitch blade, and

a secondary winding connected to discharge into the said switch blade,said secondary winding arranged to magnify the reactive effect betweenthe said switch blade and the deflecting coil, and thus, for a givenshort to open the switch.

l3. The combination of a main circuit of an alternator or bus bars, amovable switch blade therein, a deflecting coil also connect ed in thesaid main circuit, and a transtransformer to abstract current from theM0 circuit current, to diminish the time taken former whose primary coilis also in the said main circuit, said transformer having a secondarywinding arranged to discharge into the switch blade in such a way as toincrease the deflecting force on the switch blade due to the abovementioned deflecting coil, the transformer having also an auxiliary E.M. F. winding connected across one phase of the alternator or of the busbars, which auxiliary winding is arranged to reduce the reactive elfectbetween the switch blade and the deflecting coil during the normal flowof current.

In a switch intended for instantaneous automatic operation underexcessive monientary currents, the combination with a source of E. M.F., of a switch comprising a movable blade, a deflecting coil, and atransformer having a secondary coil wound for very heavy currents, saidsecondary coil arranged to discharge across the blade of the switch insuch a manner as to assist the fixed coil to deflect the switch blade,said transformer comprising a primary coil traversed by the main linecurrent during the time of the short circuit, an auxiliary primary (E.M. F.) coil, and a choking coil in series therewith, said auxiliary coilsupplied from the source of E. M. F. in such a way that its ampere turnsoverbalance the ampere turns of the main primary coil under normalworking conditions, with the object of keeping the main line current outof said blade during normal working conditions and permitting areduction of the mass of the blade and an increase in its accelerationon a short circuit occurring.

15. The combination with a main generator circuit and a switch bladetherein, of a coil in circuit with said blade and positioned to reactthereon when a current flows, a transformer comprising a primary coilconnected in series with the said circuit and a secondary coil connectedas a shunt across the blade, and so arranged that upon any abnormalincrease in the primary or main line current a greatly intensifiedcurrent is induced in this circuit in such a. direction as to assist orincrease the current in the switch blade tending to deflect the blade.

16. In circuit breaking apparatus, the combination of a main circuit, amovable switch member therein, a coil in circuit with said switch memberand positioned to react thereon when a current flows, a transformercomprising a primary coil in the main circuit and a secondary coilconnected as a shunt circuit across the said switch member and soarranged that upon any abnormal increase in the primary or main linecurrent a greatly intensified current is induced in the shunt circuit insuch a direction as to assist or increase the current in the switchblade tending to deflect said blade, said transformer having a second orauxiliary primary coil wound with many turns, a reactance, saidreactance in series with said auxiliary primary coil in a potentialcircuit from the terminals of the generator and so connected that themagnetism due to the current in said auxiliary coil will, under normalconditions, oppose and overbalance the mag- ALFRED MILLS TAYLOR.

WVitnesses ERNEST HARKER,

ETHEL M. Vans.

